A fact is the quality of being actual : actuality <a question of fact hinges on evidence>
A fact is something that has actual existence <space exploration is now a fact>
A fact is an actual occurrence <prove the fact of damage>
A fact is a piece of information presented as having objective reality
Many facts are available to be validated by direct perception.
If a fact cannot be validated directly by direct perception, a process or method of proof can be used to show or establish its relationship to the directly perceivable.